shared/sleep-config: exclude zram devices from hibernation candidates

On a host with sufficiently large zram but with no actual swap, logind will
respond to CanHibernate() with yes. With this patch, it will correctly respond
no, unless there are other swap devices to consider.

(cherry picked from commit 411ae92b407bd7b4549b205ad754bcd0e3dfd81f)

Resolves: #1763617

1 files changed, 13 insertions, 3 deletions

diff --git a/src/shared/sleep-config.c b/src/shared/sleep-config.c
index 9e4ce183d3..a1523e3f21 100644
--- a/src/shared/sleep-config.c
+++ b/src/shared/sleep-config.c
@@ -21,6 +21,7 @@
 #include "log.h"
 #include "macro.h"
 #include "parse-util.h"
+#include "path-util.h"
 #include "sleep-config.h"
 #include "string-util.h"
 #include "strv.h"
@@ -201,9 +202,18 @@ int find_hibernate_location(char **device, char **type, size_t *size, size_t *us
                         continue;
                 }
 
-                if (streq(type_field, "partition") && endswith(dev_field, "\\040(deleted)")) {
-                        log_warning("Ignoring deleted swapfile '%s'.", dev_field);
-                        continue;
+                if (streq(type_field, "partition")) {
+                        if (endswith(dev_field, "\\040(deleted)")) {
+                                log_warning("Ignoring deleted swapfile '%s'.", dev_field);
+                                continue;
+                        }
+
+                        const char *fn;
+                        fn = path_startswith(dev_field, "/dev/");
+                        if (fn && startswith(fn, "zram")) {
+                                log_debug("Ignoring compressed ram swap device '%s'.", dev_field);
+                                continue;
+                        }
                 }
                 if (device)
                         *device = TAKE_PTR(dev_field);